1. Field of the Invention
The present invention relates to an in-vehicle apparatus and an in-vehicle apparatus system, and is suitable to be applied to e.g. a car audio device for in-vehicle use.
2. Description of the Related Art
The car audio device is increasingly provided with an external input terminal compatible with a three-pole plug for audio input in order to allow connection of an external portable player.
It is becoming possible for the portable player to reproduce not only music but also a moving image. However, because the screen of the portable player itself is small, it is becoming general to output video to an external large monitor.
To view video reproduced by a portable player on a large-size monitor connected to a car audio device, an input terminal for video needs to be newly provided in the car audio device. However, it is difficult to add the new input terminal because there is a limit to the size of the front panel.
As a countermeasure against this problem, another company employs a method in which a video signal is physically separated from an audio signal by using a special four-pole plug (audio L, audio R, GND, and video) and a video input terminal is used also as an audio input terminal.
However, if such a special four-pole plug is used, the cost is increased compared with the general three-pole plug and general versatility is lost.
On the other hand, there has been proposed an in-vehicle display device in which a general AV composite jack doubles as an AV composite jack for a navigation system and switching is carried out by an analog switch circuit (refer to e.g. Japanese Patent Laid-open No. Hei 9-37189).